Method and Device for Quantizing an Information Signal

1. A device for quantizing an information signal of a sequence of information values, the information signal being an audio signal and the information values being audio values, comprising: a processor for applying a psycho-acoustic model to a block of audio values of a sequence of audio values; a calculator for calculating a version of a parameterization of a parameterizable filter based on a result of applying the psycho-acoustic model to the block; a filter for frequency-selective filtering the sequence of audio values to obtain a sequence of filtered audio values; a quantizer for quantizing the filtered audio values to obtain a sequence of quantized audio values by means of a quantizing step function which maps the filtered audio values to the quantized audio values, and wherein the quantizing step function is more steep below a threshold information value than above the threshold information value; wherein the filter for frequency-selective filtering comprises: a filter for filtering a predetermined block of audio values of the sequence of audio values with the parameterizable filter using a predetermined parameterization depending in a predetermined manner on the version of the parameterization to obtain a block of the filtered audio values.

2. The device according to claim 1 , wherein the processor for applying is formed as a determiner for determining a listening threshold for the block of audio values, and the calculator for calculating is formed such that the version of the parameterization of the parameterizable filter is calculated such that the transfer function thereof roughly corresponds to the inverse of the magnitude of the first listening threshold.

3. The device according to claim 2 , wherein the determiner for determining a listening threshold is formed to further determine another second listening threshold for another second block of audio values, and the calculator for calculating is formed to calculate a version of another second parameterization of the parameterizable filter such that the transfer function thereof roughly corresponds to the inverse of the magnitude of the second listening threshold, wherein the filter for frequency-selective filtering comprises: an interpolator for interpolating between the version of the first parameterization and the version of the second parameterization to obtain a version of an interpolated parameterization for a predetermined audio value of the predetermined block of audio values; and a processor for applying the version of the interpolated parameterization to the predetermined audio value of the predetermined block of audio values.

4. The device according to claim 3 , further comprising a determiner for determining a first noise power limit depending on the first masking threshold and a second noise power limit depending on the second masking threshold, and wherein the filter for filtering comprises an interpolator for interpolating between the first noise power limit and the second noise power limit to obtain an interpolated noise power limit for a predetermined audio value of the predetermined block of audio values, a determiner for determining an intermediate scaling value depending on a quantizing noise power caused by quantizing according to a predetermined quantizing rule and the interpolated noise power limit, and a processor for applying the intermediate scaling value to the predetermined audio value to obtain a scaled filtered audio value.

5. The device according to claim 4 , wherein the interpolator for interpolating between the first noise power limit and the second noise power limit performs a linear interpolation.

6. The device according to claim 4 , wherein the determiner for determining the intermediate scaling value comprises a calculator for calculating the root of the quotient of the quantizing noise divided by the interpolated noise power limit.

7. The device according to claim 2 , wherein the quantizer for quantizing is formed to perform quantizing responsive to a control signal.

8. The device according to claim 2 , further comprising a lossless compressor for compressing the filtered audio values into a compressed audio stream, wherein the compressor is formed to control a bit rate of the compressed audio stream and to send the control signal to the quantizer for quantizing in the case that the bit rate is greater than a control value.

9. The device according to claim 2 , wherein the quantizing step function has a flat course above the threshold information value such that filtered audio values greater than the threshold information value are quantized to a maximum quantizing step value.

10. A method for quantizing an information signal of a sequence of information values, the information signal being an audio signal and the information values being audio values, comprising the steps of: frequency-selective filtering the sequence of audio values to obtain a sequence of filtered audio values; quantizing the filtered audio values to obtain a sequence of quantized audio values by means of a quantizing step function which maps the filtered audio values to the quantized audio values, and wherein the quantizing step function is more steep below a threshold information value than above the threshold information value; applying a psycho-acoustic model to a block of audio values; and calculating a version of a parameterization of a parameterizable filter based on a result of applying the psycho-acoustic model to the block, wherein the step of frequency-selective filtering further comprises the step of: filtering a predetermined block of audio values of the sequence of audio values with the parameterizable filter using a predetermined parameterization which in a predetermined manner depends on the version of the parameterization to obtain a block of the filtered audio values.

11. A computer-readable medium having a computer program stored thereon, the computer program having program code for quantizing an information signal of a sequence of information values, the information signal being an audio signal and the information values being audio values, the program code comprising: code for frequency-selective filtering the sequence of audio values to obtain a sequence of filtered audio values; code for quantizing the filtered audio values to obtain a sequence of quantized audio values by means of a quantizing step function which maps the filtered audio values to the quantized audio values, and wherein the quantizing step function is more steep below a threshold information value than above the threshold information value; code for applying a psycho-acoustic model to a block of audio values; and code for calculating a version of a parameterization of a parameterizable filter based on a result of applying the psycho-acoustic model to the block, wherein the code for frequency-selective filtering the sequence of audio values includes code for filtering a predetermined block of audio values of the sequence of audio values with the parameterizable filter using a predetermined parameterization which in a predetermined manner depends on the version of the parameterization to obtain a block of the filtered audio values.